California Sees Rise in Horse Deaths due to Cardiac Failure

California racing saw a sharp increase last year in the number of fatalities due to cardiac failures. Eleven horses were reported as having died in this manner during fiscal year 2012 (July 1 through June 30) compared with six for the same period in 2011 and four in 2009, according to a California Horse Racing Board (CHRB) annual report.

Equally concerning is that a reported seven out of the 11—or 64%—of the horses that died from cardiac failure statewide had been stabled with leading Southern California trainer and Hall of Famer Bob Baffert, according to several trainers and exercise riders who watched the horses drop during training hours.

Baffert did not respond to questions by email or return phone calls. The identifications of the horses that died have not been released by the CHRB.

Cardiac failure in Thoroughbred racehorses is a relatively rare occurrence, according to trainers and racetrack veterinarians. A study published in 2010 in the Equine Veterinary Journal on sudden death in racing Thoroughbreds found it was responsible for 9% of fatalities in California. This same study showed 96 reported sudden deaths between Feb. 1990 and Aug. 2008 in California among Thoroughbreds while they were exercising, or an average of five per year. During the 18-year period, a total of five were reported in Pennsylvania; 23 in Victoria, Australia; 16 in Sydney; four in Hong Kong; and none in Japan.

"It's disturbing and unnatural," said one trainer based at Betfair Hollywood Park, in Inglewood, Calif., who spoke on the condition of anonymity about the number of sudden deaths he's seen. One of his own horses nearly collided with one of Baffert's horses that collapsed in front of it while galloping in the morning at Hollywood. "I've been in training for 25 years and not had one. I don't know why it's happening but it can't continue. It is putting horses and riders at risk."

"It is more than a trainer should have," added another Hollywood-based trainer, who would only speak if his name was withheld out of fear of retribution. Baffert has the largest racing stable in California and one of his clients is Mike Pegram, chairman of the Thoroughbred Owners of California.

"Bob has a lot of horses so, of course, he has more of everything, but this is more than any one trainer should have," the trainer said. That so many of Baffert's horses had died suddenly during training hours was confirmed by three other trainers and an outrider.

A state lab has conducted necropsies on the all horses but has not determined a reason for the rash of sudden deaths.

"We have not been able to find the cause," said Francisco Uzal, DVM, PhD, of the California Animal Health and Food Safety Laboratory System (CAHFS), during a Feb. 20 meeting of the CHRB Medication Committee. "We have done extensive toxicological studies. We have done, of course, all sort of other things—pathology and histology. We don't know what's going on."

During a CHRB Medication and Track Safety Committee meeting April 10, it was disclosed that a trace of anticoagulant rat poisons had been found in two horses.

"The toxicologist was unclear of its significance it was so low, but both horses had internal hemorrhage problems so they took it seriously," said Rick Arthur, DVM, the CHRB medical director. "Neither of those rodenticides were used by the pest control agencies at the respective track where they are at."

Also during the April 10 meeting, Arthur dismissed any claim that California was seeing an increase in sudden deaths attributed to a cardiovascular/pulmonary cause. He said the state has about 20 cases per year and is on track to see 21 or 22 in 2012-13. In his numbers presented to the committee, he did not break out those attributable to just cardiac failure.

"About 30% of these cases are unexplained," Arthur said.

Mike Marten, spokesman for the CHRB, issued the following statement regarding the sudden deaths: "Dr. Uzal and Dr. Arthur raised the issue of numerous sudden deaths during the Feb. 20 presentation to the medication committee. The CHRB takes this seriously and in addition to the work being done by Dr. Uzal's group and Dr. Arthur, we have assigned an investigator to look further into the matter."

When contacted prior to the April 10 meeting, Arthur told TheBlood-Horse he could not talk about specific cases but did say in an email that the state does drug testing, toxicology, and conducts special examinations of the heart in all sudden death cases.

"I personally review every necropsy report from CAHFS and as equine medical director consult with the pathologists or Dr. Uzal routinely," Arthur wrote. "There is much that slips by our notice, nevertheless; anomalies either by surface, track, trainer, or diagnosis, or any combination thereof."